No update last week. I spent my shop time in a basement replacing a sump pump. But we did receive Mike's box of goodies as already posted. So the task is to get enough workbench space available to start work on the engine. First thing was to finish up the pigtails on the instruments. I ordered a new back for the speedo as the one we had was deeply scratched. But the new ones from Honda are multipurpose, with a large cutout to accommodate several K series. Just didn't look right. In anticipation of not liking that back I sent the OEM one to Brown's hoping they can overcome the deep scratch.
After practicing on an old instrument we put the Heat shrink sheathing I'd found on eBay on the pigtail. Mt fear was that at 1/2in it wouldn't shrink far enough to sheath 5 wires. Turns out no prob.
Practice:
Tip: use a heat gun on high for about 20 seconds.
Nice fit with the grommet.
AS reported the NOS OEM tach sheathing was hard as rock. IT was pulling out of the grommet and had the appearance of near breaking. I bit my lip and we replaced the sheathing on it as well. Settled well insode the cover, not to pull out. Nice and flexible, no chance of cracking.
Mike was concerned that the sleeves he used would it in my cases. So we confirmed all is OK there.
Had a low level crisis. Got a knock pin cocked in the hole, who among us hasn't. Nearly destroyed it getting it out. Dressed the hole with a tube of emery paper, slipped the next one in no problem.
Just a review for those who may wonder why we port the CB750 head. Here's one example. You can see a bump in the port of this stock head. The light is reflected back. Its as though someone put a thumb print in the aluminum when it was soft. Very disturbing to efficient flow.
Grind it out, smooth and taper. IF you stick your finger in a stock intake port you'll find many such anomalies that are removed by porting. There is only so much a manufacturer can do before the bean counters say move on. Porting is done nearly completely by hand, which the manufacturer just can't afford to do.
Final consideration for the evening. The 4 cam bearing hold down stud came to me in a bag. Me and these have real bad karma. This engine (different head now) leaked out of these stud holes to an obscene amount. Many here have had the same problem. Replacing these studs in a way to prevent leakage eluded me, as I had stripped the holes, helicoiled them (big no-no) stripped those, replaced with 1/4-28s, and well, gave up.
These holes are nice and fresh and Mike says use a Teflon paste thread sealer and no leaks should occur. I'm confident this is so. Here's the stud and you can see where its threaded hole actually goes thru the head and opens to the atmosphere in the plug cavity.
Next week we hope to get the rings on the pistons, pistons on the rods and maybe the cyls on. I only have so much time each week to work on it, but we'll continue the relentless march to completion!
